LA APEX Flashcards
Highest to lowest Cp
Iv
Tracheal
Interpleural
Intercostal
Caudal
Brachial plexus
Femoral
Sciatic
Subq
What determines final plasma concentration?
total dose
NOT concentration/ speed of injection
Most common cause of toxic plasma concentration of LA?
Inadvertent iv injection
Most common symptom of LA toxicity
Seizures
EXCEPT Bupivicaine- cardiac arrest
LAST if more common in what neuraxial technique?
Peripheral nerve blocks
Not epidural
Early and late lido toxicity signs CNS and heart
CNS- analgesia, tinnitus, blurry vision, numbness, then seizures and LOC, then coma
Cardiac- hypotension/ myocardial depression then respiratory arret then cardio collapse
What increases risk of CNS toxicity LA
Hypercarbia, acidosis, hyperkalemia
They increase blood flow (and drug) to brain
What decreases risk of CNS LA toxicity?
hypokalemia
Alkalosis
CNS depressant
Cocaine OD Tx
NTG
Mixed a and b blockers- coreg/ labetalol?
Cocaine should be avoided with maoi, tca, and sympathomimetic drugs
How can u reduce risk of LAST?
Test dose and incremental dosing with periodic aspiration
Tx of LAST
Airway- fio2 100, hypoxia and acidosis will worsen
Benzos- then succ to stop muscle contraction, avoid prop bc heart effects, no prop as lipid emulsion therapy
ACLS mod- low dose only of epi bc reducing the effectiveness of lipid therapy, avoid vaso, use AMIO, avoid lido and procainamide
Lipid emulsion therapy- bolus, infusion for 15 minutes after pt regains consciousness, max 12ml/kg
Avoid BB and CCB for cardiac effects
Max dose of lidocaine for regular vs tumescent anesthesis
Regular- 500 mg or 7mg/kg
Tumescent- 50mg/kg or about 3500 mg, which is debatable
Most common cause of death in tumescent anesthesia/ lipo
Pulmonary embolism
When is GA indicated for tumescent anesthesia?
If tumescent >2L due to risk of fluid shiftt, pulmonary edema
HGB is built from what subunits
4- 2a and 2b with heme groups
